Azo dyestuffs and process of making same



iii

Patented Mar. 17, 1925.

UNITED STATES 0 1,529,921 PATENT OFFICE.

AUGUST HEINRICH SCHOBEL, OF BASEL, SWITZERLAND. ASSIGNOR TO SOCIETY OF GHEMICALINDUSTRY IN BASLE, OF BASEL. SWITZERLAND.

.AZO DYESTUFFS AND PROCESS OF MAKING SAME.

No Drawing.

T 0 all whom it may concern Be it known that I. Atous'r Hummer! SoHonEL, a citizen of the Swiss Confederation, and residing at Basel. Switzerland, have invented new and useful Improvements in Azo Dyestuffs and Processes of Making Same, of which the following is a full. clear. and exact specification.

This invention relates to new dyestuffs which are particularly valuable for produc ing: fast colours in chrome printing.

In specification of U. S. Patent No. 1,437,758 there are described violet to brown. dycstufi's for chrome printingwliich are obtained by coupling resorcylic acid with di azo-compounds derived from l-amino-Z-hydroxynaphthalene-4-sulphonic acid. The present invention relates to an improvement in or modification of that described in U. S. Patent No. 1, 437,7 58.

According to the present invention dyestufl's which are particularly valuable for chrome printing are obtained by coupling, resorcylic acid with one or two molecular proportions of the same or different diazocompounds, one at least of which is an orthohydroxy-diazo-compound of the benzene series.

The dyestufi's are dark powders soluble in water to yellow-brown to brown-red solutions. In concentrated sulphuric acid they dissolve to yellow-brown to red-brown and blue solutions. In chrome printing on cotton they produce brown tints of very different shades and remarkably fast.

The following examples illustrate the invention without, however, limiting the same, the parts being by weight Example 1.

The new dyestufi is a dark powder, soluble in water to a brown-red solution, which becomes somewhat more red on addition of sodium carbonate. In concentrated sulphuric acid it dissolves to a yellow-brown so- Application filed May 10.

1924. Serial No. 712,450.

lution. In hrome printing on cotton it produces full redbrown tints of very good'fast ness to washing and soaping and good fastness to chlorine and light.

Example 2.

The diazo-conipoimd from 15.4' parts of 4-'nltro-2ammo-l-hydroxybenzene is allowed to flow into a solution of 7.7 parts of resorcylic acid and-3O parts of calcined sodium carbonate. The dyostufi' is then salted out.

It is a dark powder. soluble in water to a red-brown solution which becomes somewhat more red on addition of sodium carbonate. In concentrated sulphuric acid it dissolves to a. red-brown solution. In chrome printing on cotton it yields violet-brown tints of good fastness'.

Example 3.

Dlllllh' acid it dissolves to a red solution.

When chrome printed on cotton it produces violet brown tints of very good fastness.

Example 1;.

The diam-compound from 22.3 parts-of 1 -hydroxy- 2 -amino- 4 -chlorobenzene-5-sulphonic acid is allowed to flow into a concentrated solution of 7.7 parts of resorcylic acid. After stirring for some hours at 1520 C. coupling is complete, whereupon the dyestufi' is precipitated by neutralizing the liquid with mineral acid. It dissolves in water to a brown-yellow solution which becomes red on addition of sodium carbonate. Concentrated sulphuric acid dissolves it to a blue-red solution. In chrome printing it produces on cotton violet tints of very good fastness.

I Example 5.

19.8 parts benzene-(i-carboxylic the usual manner with of 1-hydroxy-2-amino-4-nitroacid are diazotized in 15 parts of hydro is filtered, pressed and dried.

In concentrated sulphuric acid it dissolves to an orange-red solution. In chrome printing on cotton it yields yellow-brown tints of good fastness.

Example 6.

The diazo-compound prepared in the usual manner from 19.8 parts of 1--hydroxy- 2-amino-et-nitrobenzene-G-carboxylic acid, 15 parts of hydrochloric acid and 6.9 parts of sodium nitrite, is run into a concentrated solution of 7.7 parts of resorcylic acid. After stirring for some hours the diazo-compound has disappeared. The dyestufi is precipitated by saturating the solution with common salt. l

The new dyestufi' dissolves in water to a yellow-brown solution becoming a redbrown on addition of caustic soda lye. In concentrated sulphuric acid it dissolves to a brown-red solution. When printed with chromium acetate on cotton there is produced a brownish-yellow of good fastness.

sam le 7.

sodium carbonate is run the diam-compound from 223 parts of 1-hydroxy-2-amino-4- chlorobenzene-5-sulphonic acid, 6.9 parts. of

sodium nitrite and partsof hydrochloric.

acid. When coupling is complete a further 10 parts of calcined sodium carbonate are added and there is stirred into'the mixture at ordinary temperature the diaz'o-compound fronr 19.9 parts of Lhy'droxy 2- amino-4:S-dinitrobenzene and 6.9 parts of sodium nitrite. After stirring for some hours the coupling is complete and the d estutf is precipitated from a boiling hot so ution by adding common salt. The dyestuff It dissolves in- Water to a brown solution becoming brown-red on addition of caustic alkali. In concentrated sul huric acid it dissolves to a brown-red so ution. When chrome printed on cotton it gives a beautiful violet-brown of very good fastness to washing, soaping and chlorine.

H I Example '8.

The diazo compound from 19.8 parts of 1 hydroxy 2 amino 4-nitrobenzene-6-carboxylic acid is coupled with 15.4 parts of resorcylic acid in presence of parts of calcined sodium carbonate. When the coupling iscomplete a further 10 parts of cal Example .9.

The diazo-compound obtained from 23.3 parts of 1hydroxy-2-amino-l-sulphobenzene-(S-carboxylic acid, 6.9 parts of sodium nitrite and 15 parts of hydrochloric acid is allowed to flow into an ice-cold solution of 15.4 parts of resorcylioacid and 40 parts of calcined sodium carbonate. When the formation of the dyestufl is complete, coupling is repeated with the diazo-compound from 14.3 arts of e-na'pthylamine. After stirring'm the cold for some hours the coupling is complete and the dyestufi' may be isolated in the usual manner.

'It dissolves in water to a yellow-brown solution "which becomes redder on addition ofcaustio alkali. In concentrated sulphuric When printed on acid it dissolves to a blue solution. When chrome printed on cotton it yields a yellowbrown of good fastness. -What I claim is 1. The process for producin 'azo-dyestufis which are particularly a apted for chrome printing by coupling one molecule of resorcylic acid with at the maximum two -molecules of diazo-compounds, one at least of which being an ortho-hydroxy-diazocompound of the benzene series.

2. The process for producing azo-dyestuffs which are particularly adapted for chrome printing by coupling one molecule of resorcylic acid with atthe maximum two molecules of ortho-hydroxy-diazo-compounds of the benzene series.

3. The process for producing azo-dyestufis which are particularly adapted for chrome printing by coupling one molecule of resorcylic'acid with one molecule of an ortho-hydto'xy-diazo-compound of the hem zene series.

'4. The process for producing azo-dyechrome printing by coupling one molecule stuffs which are particularly adapted for chrome printing by coupling one molecule formula R, (--N:N--R

wherein R, stands for the residue of resorcylic acid, R for an aromatic residue.

n for a whole number smaller than 3, and in which at least one of the aromatic residues It. P2111183 a hydroxy group which adheres in ortho-position to the azo-bridge. which -wherein.R stands for the residue of resdyestuffs form dark powders soluble in water to yellow-brown to brownred solutions and dissolving in concentrated sulphuricacid to yellow-brown to red-brown and blue solutions, producing, whenchrome printed on cotton, brown tints of very different shades and remarkably fast.

7. The herein described new dyestuffs which are obtained by coupling one molecule of resorcylic acid with at the maximum two molecules of ortho-hydroxyoiazo-compounds of the benzene series, which dyestuffs correspond to the general formula:

wherein R stands for the residue of resorcylic acid, It; for an aromatic residue which carries a hydroxy group adhering in ortho-position to the azo-bridge, and n a whole number smaller than 3, which dyestuffsform dark powders soluble in water to yellow-brown to brown-red solutions and dissolving in concentrated sulphuric acid to wherein R stands for the residue of resorcylic acid and R for'an aromatic residue which Carries a hydroxy group adhering in willie-position to the azo-bridge, which dyes1 ulfs form dark powders soluble in water to yellow-brown to brown-red solutions and dissolving in concentrated sulphuric acid to yellow-brown to red-brown solutions, pro ducing when chrome printed on cotton brown tints of very different shades and reniarkably fast.

9. The herein described new dyestuffs which are obtained by coupling one molecule of resorcylic acid with one molecule of a non-sulphonated ortho-hydroxy-diazo-con1- pound of the benzene series, which dyestuffs correspond to the general formula:

orcylic acid and R for an unsulfonated aromatic residue which carries a hydroxy group adhering in ortho-position to the azobridge, which dyestuffs form dark powders soluble in water to yellow-brown to brownred solutions and dissolving in concentrated sulphuric acid to yellow-brown to red-brown solutions, producing when chrome printed on cotton brown tints of very different shades and remarkably fast.

10. The herein described new dyestufi which is obtained by coupling one molecule of resorcylic acid with one molecule of diazotized 4-nitro-2-amino-l-hydroxybenzene corresponding to the general formula:

wherein R stands for the residue of resorcylic acid andR for a benzene nucleus which carries an Ol-I group adhering in 2- position and an NO group adhering in 5- position to the azo-bridge, which dyestufl forms a dark owder soluble in water to a brown-red solu ion and in concentrated sulphuric acid to a yellow-brown solution, and producing when chrome printed on cotton full red-brown tints of very different shades and remarkably fast.

In witness whereof I have hereunto signed my name this 28 day of April, 1924, in the presence of two subscribing witnesses.

AUGUST HEINRICH SCHOBEL. Witnesses:

MADELEINE SrENoum,

AHAND BRAUN. 

